JP2000027727A - Fluid supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To minimize pressure drop in a hydraulic operating electronic control system by arranging an operation fluid supply device between a fluid rail and an injector, and thereby arranging the fluid rail near the injector. SOLUTION: A fluid rail 109 and a fluid rail support device are provided. The fluid rail 109 forms an operation fluid reservoir 124. An operation fluid outlet 129 connectable to an operation fluid inlet of an injector 104 is formed for the communication of the operation fluid. The fluid rail support device can be attached to an engine. When it is attached, the fluid rail 109 is arranged on an upper side of the operation fluid inlet of the injector 104 at the time of use.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for supplying a high-pressure fluid, and more particularly to an apparatus for supplying a working fluid to a hydraulically operated electronically controlled injector of an internal combustion engine, and an engine having the same.

[0002]

BACKGROUND OF THE INVENTION Hydraulically actuated electronically controlled injection (HEUI) systems use high pressure pumps to supply hydraulic fluid, preferably "borrowed" oil from the engine's lubrication system, to a fluid rail (manifold). Is done. Hydraulic oil is stored in the fluid rail and is prepared to operate the engine injector under electronic control.

[0003] Since each injector typically includes an augmentation piston having an upper portion that is larger in diameter than the lower portion, the pressure of the working fluid acting on the upper portion during injection increases the pressure of the fuel contained below the lower portion. Strengthen. The electronic control valve controls the pressure of the working fluid in the fluid rail up to about 230 bar, and correspondingly the fuel pressure in the injector is increased up to about 1500 bar depending on the required operating characteristics of the engine. You.

[0004] Prior art HEUI systems require that the fluid rails be located remotely from the injectors of the engine, the fluid rails being connected to each injector via tubing or another type of passage. I have. The reason is that it is necessary to access the injector clamp device. But,
Separating the rails and injectors creates an undesired pressure drop between these parts, creating some potential leaks and compromising the size of the engine casing.

[0005] An example of the prior art relating to the above disadvantages is shown in FIG.
And U.S. Pat. No. 5,496,612. In each of these systems, the fluid rail is mounted on the cylinder head at a location remote from the injector location. This requires the use of relatively long fluid transfer lines (U.S. Pat. No. 5,969,612 or the rail branch lines in the jumper block of FIG. 1) to transfer high pressure fluid from the manifold to the injector. For this reason, there is a possibility that the above-described problems such as leakage and pressure drop may occur.

[0006]

An object of the present invention is to provide a HEUI
In the case of systems, providing a working fluid supply between the fluid rail and the injector, where the fluid rail is located in close proximity to the injector so that the pressure drop is minimized It is in.

[0007] It is another object of the present invention to provide a working fluid supply device that minimizes the number of leak paths. Yet another object is to provide a compact working fluid supply with minimal engine jacket dimensions. It is yet another object of the present invention to provide a working fluid supply device in which removal of the injector for servicing only slightly interferes with other components of the high pressure fluid supply system.

[0008]

According to one aspect of the present invention, an apparatus for supplying high pressure working fluid to a hydraulically operated electronically controlled injector of an internal combustion engine includes a fluid rail and a fluid rail support. A fluid rail forms an operating fluid reservoir and has an outlet connectable to a working fluid inlet of the injector for communicating the working fluid, and the fluid rail support device is attached to the engine. When enabled and the support device is mounted, the fluid rail is configured to be above the working fluid inlet of the injector in use.

In this configuration, the fluid rail is located above the injector and can be located immediately adjacent to the injector, so that the fluid rail is fixed to the cylinder head at a considerable distance from the injector. The pressure drop seen in the prior art is reduced. This also opens several possibilities for clamp and injector design, which also facilitates removal of the injector during maintenance and minimizes obstruction to the high pressure fluid supply system itself.

[0010] This type of engine can have a rocker box located on the cylinder head of the engine. Alternatively, the rocker box can be formed by a wall integral with the cylinder head or a wall extending upward from the cylinder head. Preferably, the apparatus for supplying high-pressure working fluid further comprises a rocker box, which is engageable with or formed by a wall extending upwardly from the top surface of the engine cylinder head. And also includes an integral fluid rail support.

Preferably, the fluid rail support is in the form of a multi-post. Preferably, the fluid rail has a plurality of fluid outlets. This allows a single fluid rail to supply working fluid to multiple injectors. The number of fluid outlets corresponds to the number of injectors for which the fluid rail supplies working fluid.

As mentioned, engine lubricating oil is a preferred fluid for injector operation. If the engine's fuel were to be used to operate the injector, a safety device would be needed to return fuel from the booster to the tank. In addition, the increase in temperature inside the fuel caused by the augmentation can harm the operation of the engine if the fuel is subsequently injected into the engine.

If a lubricating oil is used for operation, the oil is subsequently discharged from the injector after the operating process, returned to the engine sump, cooled by a conventional engine oil cooling system and then re-used. used. An oil drainage device is preferably provided to return the hydraulic oil to the oil sump of the engine. If the injector is located in the enclosed volume of the engine, a conventional engine drain can be used to return the oil.

According to a second aspect of the present invention, a hydraulically actuated fuel injector for an internal combustion engine includes an injector, the previously described device for supplying working fluid to the injector, and the injector fixed in position. A clamping device including a clamp having a first end also adapted to engage the injector body, and a clamp support member adapted to position the clamp in a fixed position on the engine. Clamping force applying means for engaging the clamp so as to apply a clamp load to the injector body.

To ensure that there is sufficient space for fluid rail placement in the immediate vicinity of the injector, the clamp support is
Preferably, it is spaced from the clamp first end, but more preferably, it is substantially located at the clamp second end. The clamping force applying means is adapted to engage the clamp at a location spaced from the clamp first end, and more preferably, substantially to engage the clamp at the clamp second end. When used by attaching to an engine,
Preferably, the fluid rail support device is configured to position the fluid rail at a position above the clamp arm between the injector and the clamping force application means.

The clamp and the fluid rail are engaged with each other at a rolling contact point so that a fulcrum can be obtained. Through this fulcrum, a clamp load is applied from the clamping force applying means to the first clamp end. Part to the injector body. The fulcrum is preferably located between the first end and the clamping force applying means. Also, the fulcrum preferably includes a curved clamp upper surface portion adapted to engage the flat lower surface of the fluid rail.

[0017]

BRIEF DESCRIPTION OF THE DRAWINGS An embodiment of the invention will be described below with reference to the accompanying drawings. Referring to the drawings, FIG. 1 shows a known hydraulically operated electronic control unit injector (HEUI) and a known hydraulic oil supply. It can be seen from this configuration that the hydraulic oil supply 22 having the high-pressure hydraulic oil rail 24 is attached to the cylinder head 1. A rocker arm base 23 is mounted on the upper surface of the hydraulic oil supply, and a jumper block 32 is mounted on this base.

The high-pressure hydraulic oil rail 24 is provided with the hydraulic oil supply 2
2, fluidly connected to the transfer block 26 via passages 29, 33, 34 in the rocker arm base 23 and the jumper block 32. The transfer block 26 mechanically couples the jumper block to the injector 4 and has a fluid connection. The injector 4 is fixed to the engine by the clamp 12, which itself is fixed by at least one screw fixing member 35 that engages with the hydraulic oil supply 22.

This known device has several disadvantages: That is, the hydraulic oil supply body needs to be machined at least on the upper and lower surfaces, and then needs to be hermetically fixed to the cylinder head of the engine. That the path is implicit, that any attempt to minimize engine width is a compromise with the external dimensions of the oil supply,
Further, to access the injector clamp 12 for injector maintenance, the jumper block 32 must be removed,
Therefore, sealing of the jumper block by the rocker arm base is hindered.

In US Pat. No. 5,496,612, the disclosed injector clamp can be removed and replaced without disturbing the hydraulic oil supply system, but removing and re-installing the injector requires a rail. The branch passage 26 must be removed, which increases the risk of oil leakage after reassembly.

Furthermore, the number of sealing boundaries (interfaces) of the hydraulic oil supply system of said patent is less than those of the known device of FIG. 1, but the angular misalignment at each end of the rail branch passage. A divergent tubing connection is used to adjust the
It is not as robust as a clamped ring seal between two rigid members.

The disadvantages mentioned in the three paragraphs are:
It can be eliminated or mitigated by the present invention, and the present invention is described below with reference to FIGS.

A locker box 106 is mounted on the upper surface 105 of the cylinder head 101 of the engine. In this embodiment, each engine has one injector 1
It has a few cylinders with 04. The locker box defines a volume 107 within which is contained one or more gas exchange valves that operate mechanisms 108 (only some of which are visible in the figure), and a volume 1
Above 07, the device of the present invention is included. The gas exchange valve that operates the mechanism 108 is conventionally mounted on the engine, and then the device of the present invention is mounted in the manner described below.

The hydraulic oil rail 109 defining the internal reservoir 124 has one hydraulic oil inlet 135 and a small number of hydraulic oil outlets 129 corresponding to the number of injectors supplied with hydraulic oil.
And The pillar 136 is the locker box 106
, And is formed integrally with the locker box. The hydraulic oil rail 109 is attached to the column 136 and is fixed to the column by a screw fixing member 137. Alternatively (not shown), the hydraulic oil rail can be fixed by a screw fixing member that penetrates into the cylinder head through the rocker box, so that both the hydraulic oil rail and the rocker box can be fixed to the engine. . In this embodiment, the injectors are arranged in a straight line, and the hydraulic oil rail 109 is arranged in parallel with the arrangement plane.

The hydraulic oil inlet 135 in the hydraulic oil rail is connected to a hydraulic oil supply passage 138 in the rocker box, and its boundary (interface) is made oil-tight by a seal ring 141 or other conventional means. ing. A conduit 139 from a hydraulic oil pump (not shown) to the rocker box passage is provided in a conventional manner.

Following installation of the hydraulic oil rails, each injector 104 with an electronic control valve 113 is located in the cylinder head and tightened down by clamps 112 until the required axial load is obtained. Can be One end 116 of clamp 112 is adapted to engage shoulder 117 of injector 104. The raised portion 120 on the upper surface of the clamp 112 is engaged with a pad 121 on the hydraulic oil rail 109 as a fulcrum. The clamp 112, and thus the injector 104, is fixedly held at the outer end of the clamp via a screw hole 111 by a clamp support member consisting of a screw 114, and the outer end of the clamp is fixed in place by a lock nut 115. This configuration expands the space available for mounting the hydraulic oil rail immediately adjacent injector 104. It should be noted that the clamping device and the clamping method are the subject of another patent application by the present applicant.

Next, the hydraulic oil transfer block 1 is connected so that the hydraulic oil rail 109 is mechanically connected to each injector via passages 127 and 129, and is fluidly connected.
26 is positioned and fixed to the injector by a screw fixing member 125 and to the hydraulic oil rail by a screw fixing member 140. Even if hydraulic oil leaks out of the fluid interface into the volume 107 defined by the rocker box 106 and is returned to the engine sump (not shown) in a conventional manner, the oil leak will not affect the performance of the injector. A seal with a seal ring or other conventional means is necessary because it may harm the horn. The cover 128 is then attached to the locker box 106 in a conventional manner.

If the injector needs servicing, the locker box cover 128, transfer block 126, injector clamp 112, and injector 104 can be easily removed. Except for removal and re-installation of the transfer block, no part of the HEUI for operating the hydraulic oil supply system is disturbed during injector maintenance.

[Brief description of the drawings]

FIG. 1 is a diagram of a known HEUI system attached to an engine having a known injector hydraulic oil supply and an injector clamp device.

FIG. 2 is a sectional view of an upper part of an engine to which the device of the present invention is attached.

FIG. 3 is a side view of the apparatus of FIG. 2 with the top cover and gas exchange valve removed for clarity.

FIG. 4 is a plan view of the device of FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder head 4 Injector 12 Clamp 22 Hydraulic oil supply 23 Rocker arm base 24 High pressure hydraulic oil rail 26 Transfer block 32 Jumper block 101 Cylinder head 106 Rocker box 108 Gas exchange valve operating mechanism 109 Hydraulic oil rail 112 Clamp 113 Electronic control valve 117 Shoulder of injector 120 Ridge 124 Internal reservoir 126 Transfer block 128 Cover 129 Hydraulic oil outlet 135 Hydraulic oil inlet 136 Column base

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02M 61/14 320 F02M 61/14 320A // F02M 55/02 350 55/02 350H

Claims (16)

[Claims] An apparatus for supplying high pressure working fluid to a hydraulically actuated electronically controlled injector of an internal combustion engine, comprising a fluid rail (109) and a fluid rail support device, wherein the fluid rail is a working fluid reservoir. An injector (104) for forming (124) and communicating the working fluid
Outlet (129) that can be connected to the working fluid inlet (135)
Wherein the fluid rail support device is adapted to be mounted to an engine and, when mounted, the fluid rail (109) in use.
A device for supplying high pressure working fluid, wherein the device is located above the working fluid inlet of the injector (104). 2. A locker box (106) engageable with an upper surface of a cylinder head (101) of the engine,
And an integral fluid rail support.
An apparatus for supplying a high-pressure working fluid according to claim 1. 3. A rocker box (106) extending upwardly from an upper surface of an engine cylinder head (101) and formed by walls integral with the upper surface, the rocker box including an integral fluid rail support. Contains,
An apparatus for supplying a high-pressure working fluid according to claim 1. 4. A fluid rail support device comprising a plurality of column bases (13).
Apparatus according to any one of the preceding claims, comprising 6). 5. The device according to claim 1, wherein the fluid rail (109) has a plurality of fluid outlets (129). 6. Apparatus according to claim 1, wherein the working fluid is an engine lubricating oil. 7. The apparatus according to claim 6, wherein a drainage device is provided for returning oil to a sump of the engine. 8. A hydraulically actuated fuel injection device for an internal combustion engine, comprising: an injector (104) for supplying a working fluid to the injector according to any one of the preceding claims. A clamping device including a device, a clamping device for clamping the injector in place, a clamp (112) also having a first end (116) adapted to engage the injector body, and the clamp A fuel injection device, comprising: a clamp support member (114) adapted to position the fuel injector in a fixed position on the engine; and a clamping force applying means for engaging the clamp to apply a clamp load to the injector body. 9. The method according to claim 8, wherein the clamp support member is provided at a first end (11).
9. The fuel injection device according to claim 8, which is arranged at a distance from (6). 10. A clamp (1) wherein the clamp support member is a clamp (1).
10. The fuel injection device according to claim 9, wherein the fuel injection device is arranged substantially at the second end of the item (12). 11. The clamping force applying means adapted to engage the clamp at a location spaced from a first end (116) of the clamp (112). A fuel injection device according to any one of the preceding claims. 12. The fuel injector according to claim 11, wherein the clamping force applying means is adapted to engage the clamp at substantially the second end of the clamp (112). 13. When the fluid rail support device is used by being attached to an engine, the fluid rail support (10) is provided.
9) is located above the clamping arm between the injector (104) and the clamping force applying means.
The fuel injection device according to any one of claims 1 to 12. 14. The fulcrum is obtained by engaging the clamp (112) and the fluid rail (109) with each other at a rolling contact point. 14. The fuel injection device according to claim 13, wherein the fuel is transmitted from the addition means via the clamp first end (116) to the injector (104) body. 15. The fuel injection device according to claim 14, wherein the fulcrum is located between the first end (116) and the clamping force applying means. 16. A clamp (11) wherein the fulcrum is adapted to contact a flat lower surface on a fluid rail (109).
16. The fuel injection device according to claim 15, comprising a curved top portion of 2).